The Platform Model

The Semantic Key

Everything derives from a single three-segment key:

{project} - {env} - {service}

Segment	Role	Examples
project	Ownership boundary — domain or product area	payments, orders, platform
env	Deployment target	dev, staging, prod, mgmt
service	Individual workload or infrastructure piece	api, worker, gke-main

env is owned by Kubernetes and ArgoCD. Backstage observes env at runtime — it never defines it.

How the Key Maps Across Every System

Concept	Backstage	ArgoCD	Kubernetes	Crossplane
Ownership boundary	Domain	AppProject	project label	Claims namespace prefix
Logical product	System	ApplicationSet	namespace group <project>-*	—
Workload	Component	Application (base)	service label	—
Cloud resource	Resource	Application	infra namespace <project>-<env>-infra	Claim
Deployment instance	(observed)	Application (instance)	namespace <project>-<env>-<service>	—

Full Picture

Backstage Catalog          ArgoCD                   Kubernetes               Cloud
─────────────────────────────────────────────────────────────────────────────────────

Domain: payments      ──►  AppProject: payments  ──►  label: project=payments
│
├── System: gateway   ──►  AppSet: gateway       ──►  namespace group: payments-*
│   └── Component:    ──►  Application:           ──►  payments-dev-api
│       gateway-api        gateway-api-<env>           payments-staging-api
│                                                       payments-prod-api
│
└── Resource:         ──►  Application:           ──►  payments-prod-infra     ──►  GKE Cluster
    gcp-payments-          crossplane-payments-         Claim: gke-main              (GCP)
    prod-gke-main          prod-gke-main